Integrated receiver dryer sleeve

ABSTRACT

A heat exchanger for a vehicle is provided having a core with a set of flow tubes connected to a header. The header includes a receiver/dryer housing in fluid communication with the flow tubes. An insert assembly is received in an end of the receiver/dryer housing and includes a sleeve having a substantially smooth outer surface, a filter portion received within the sleeve, and a plug portion configured to form a substantially fluid-tight seal with the sleeve. The inner diameter of the receiver/dryer housing and the outer diameter of the sleeve are substantially equal to each other.

BACKGROUND

1. Field of the Invention

The present invention relates generally to a heat exchanger having a receiver/dryer housing. More specifically, the present invention relates to an insert assembly to be received within the receiver/dryer housing.

2. Related Technology

Condenser assemblies for automotive vehicle air conditioning systems typically include a pair of headers and a core having a plurality of tubes, through which refrigerant flows, disposed horizontally between the two headers. An inlet is disposed near an upper portion of one of the headers, and an outlet is disposed at the lower portion of either the same or the other header. Within the headers, partitions are provided to divide the interior space of the headers into more than one fluidly separate space. As a result, the refrigerant is caused to flow in a serpentine fashion making more than one path through the tubes between the headers.

Typically attached to one of the headers and in fluid communication therewith is a receiver. Refrigerant that is condensed in the core flows into the receiver where it is separated into gas and liquid portions. Because the presence of water in the refrigerant will degrade the performance and structural integrity of the air conditioning system, a dryer is often associated with or located within the receiver. The dryer contacts the liquid and vapor portion of the refrigerant facilitating the removal of water from the refrigerant. The dryer may itself be comprised of a bag or cartridge containing dryer granulates such as desiccant. After the dryer removes the water from the refrigerant, the remaining fluid flows out of an opening in the receiver/dryer housing and towards the outlet.

Also typically attached to the receiver/dryer housing is a plug portion to prevent liquid and gas from undesirably escaping the receiver/dryer housing and to force the liquid and gas out of the opening in the receiver/dryer housing. The plug portion should be precisely positioned within the receiver/dryer housing to form an effective seal with the receiver/dryer housing and in order to be properly aligned with the opening in the receiver/dryer housing. Furthermore, the plug portion should be easily positionable within the receiver/dryer housing and constructed to reduce manufacturing and maintenance steps.

Therefore, it is desirable to provide an assembly and a method of assembly to effectively and easily position the plug portion within the receiver/dryer housing.

SUMMARY

In one aspect of the present invention, a heat exchanger for a vehicle is provided, including a core having a set of flow tubes and a header connected to the set of flow tubes. The header includes a receiver/dryer housing that is in fluid communication with the set of flow tubes and receives an insert assembly having a filter/plug assembly. The filter portion extends across an opening in the receiver/dryer housing to prevent unwanted particulates and other solids from further flowing through the heat exchange system. The plug portion forms a substantially fluid-tight seal with the sleeve to prevent the liquid and gas that flows to the receiver/dryer housing from undesirably escaping the heat exchange system via the bottom of the receiver/dryer housing.

In order to improve the connection between the receiver/dryer housing and the filter/plug assembly, a sleeve is provided within the receiver/dryer housing. More specifically, the sleeve includes an outer diameter substantially equal to the inner diameter of the receiver/dryer housing and forms a press-fit engagement between the respective components. The two components are further brazed together to form a more effective engagement. The ease and precision at which the filter/plug assembly is inserted within the sleeve may be improved by providing a threaded engagement between the sleeve and the filter/plug assembly.

In another aspect of the invention, the sleeve includes a cylindrical portion and a tapered portion, wherein the cylindrical portion has a greater diameter than the tapered portion. The tapered portion further includes an arcuate profile so as to improve the flow into the filter portion. More specifically, the inner diameter of the tapered portion is preferably substantially equal to the inner diameter of the filter portion. The sleeve also includes a shoulder portion having an outer diameter being greater than the outer diameter of the cylindrical portion. The shoulder portion contacts a bottom edge of the receiver/dryer housing to provide a hard-stop for the connection between the sleeve and the receiver/dryer housing.

In yet another aspect of the invention, the filter/plug assembly includes a standoff portion to engage the dryer element and prevent the dryer element from undesirably migrating into the sleeve.

Further objects, features and advantages of this invention will become readily apparent to persons skilled in the art after a review of the following description, with reference to the drawings and claims that are appended to and form a part of this specification.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows two cross-sectional view of a portion of a heat exchanger having a header, a receiver/dryer housing, and an insert assembly embodying the principles of the present invention; and

FIG. 2 is an exploded view of the insert assembly and the header shown in FIG. 1.

DETAILED DESCRIPTION

Referring now to the drawings, FIG. 1 shows a heat exchanger 10 embodying the principles of the present invention. The heat exchanger 10 includes a core 12 having a set of tubes 14 extending from a header at a first end (not shown) to a second end 16 for carrying a fluid such as refrigerant. A header 18 is connected to the second end 16 of the core 12 so as to be in fluid communication with the set of tubes 14 and to receive the refrigerant. The header 18 is separated into a plurality of sections by dividers 20 in order to cause the refrigerant to flow through various sections of the core 12 in a serpentine fashion. The core also includes a plurality of fins 22 extending between respective tubes 14 to promote heat transfer between air flowing across the heat exchanger and the refrigerant.

The header 16 shown in FIG. 1 includes a manifold 24 that is in fluid communication with the refrigerant via a plurality of openings 25 for receiving the tubes 14. The manifold 24 is constructed as a semi-circular portion of a tube and is connected to a receiver/dryer housing 26 along its longitudinal edges to define a manifold chamber 28 in fluid communication with the core 12.

The receiver/dryer housing 26 is a generally cylindrical body defining a receiver/dryer chamber 30 that is in fluid communication with the manifold chamber 28 via an opening 32 in the receiver/dryer housing 26. More specifically, the opening 32 is aligned with the manifold 24 so as to receive fluid from the manifold chamber 28.

As discussed above, the presence of water in the refrigerant will degrade the performance and structural integrity of the air conditioning system. Therefore, a dryer element 34 is preferably located within the receiver/dryer chamber 30 to contact at least the liquid and vapor portion of the refrigerant and to facilitate the removal of water from the refrigerant. The dryer element may 34 include a bag or a cartridge containing dryer granulates, such as desiccant.

The receiver/dryer housing 26 includes a second opening 36 to permit the refrigerant to flow from the receiver/dryer chamber 30 into a second manifold chamber 38 and back across the core 12 to a heat exchanger outlet (not shown). The second manifold chamber 38 is defined by the divider 20, the manifold 24, and a second divider 40 located near the bottom of the manifold.

In order to direct the refrigerant into the second manifold chamber 38 and to prevent the refrigerant from undesirably exiting the bottom of the receiver/dryer housing 26, an insert assembly 42 is received within the end of the receiver/dryer housing 26. More specifically, the insert assembly 42 includes a plug portion 44 that forms a substantially fluid tight seal and prevents refrigerant from undesirably exiting the receiver/dryer housing 26; a filter portion 46 to screen out particulates and other undesirable solids from the heat transfer fluid; 10; and a sleeve 48 to precisely and easily position the plug 44 and filter portions 44, 46 within the receiver/dryer housing 26. The plug portion 44 and the filter portion 46 preferably form a unitary filter/plug assembly 50, as shown in FIG. 1, that functions both as a plug and as a filter. Alternatively, the plug portion 44 and the filter portion 46 may be individual components integrally connected with each other. The filter/plug assembly 50 is preferably formed from a non-corrosive material, and is more preferably formed from a nylon material such as Nylon 66.

The filter/plug assembly 50 includes a screen 52 defining the outer surface of an upper portion 54 (shown in FIG. 2) of the filter/plug assembly 50 in order to trap particulates and other solids within the filter portion 46. In order to maximize its effective surface area, the screen 52 preferably wraps around support posts 56 extending from a lower portion 58 (shown in FIG. 2) of the filter/plug assembly 50.

In order to force the refrigerant to flow through the filter portion 46, the filter/plug assembly 50 further includes a sealing ring 57 that forms a substantially fluid-tight seal with the sleeve 48. More specifically, the sealing ring 57 extends around the support posts 56 and is connected to the filter portion 54 to prevent the refrigerant from exiting the filter/plug assembly 50 without flowing through the screen 52. The outer surface of the sealing ring 57 is preferably the same size and shape as the inner surface of the sleeve 48 such as to form a radial seal. Furthermore, the sealing ring 57 includes a tapered portion 59 to engage the upper portion of the sleeve, which has an arcuate portion as discussed in further detail below.

The plug portion 44 comprises the lower portion 58 of the filter/plug assembly 50. In order to position the filter/plug assembly 50 at its desired position with respect to the receiver/dryer housing 26, and in order to form a substantially fluid-tight seal, the plug portion 44 includes a threaded section 60. The plug portion 44 also includes an O-ring or sealing ring 62, located within a groove 63 in the outer surface of the plug portion 44 to improve the fluid-tight seal.

Also provided on the filter/plug assembly 50 is a standoff 64 that contacts a portion of the dryer element 34 to prevent the dryer element 34 from migrating into the filter/plug assembly 50. More specifically, the standoff 64 extends upwardly from the lower portion 58 of the filter/plug assembly 50 and contacts an end section 66 of the dryer element 34. As shown in FIG. 2, the standoff 64 extends beyond the top 65 of the filter/plug assembly 50 and includes an X-shaped cross-section so as to sufficiently engage the end section 66 regardless of its orientation. In order to substantially support the weight of the dryer element 34, the end section 66 is preferably a portion of the dryer element bag that has been folded into a stiff flange.

The sleeve 48 is located between the filter/plug assembly 50 and the receiver/dryer housing 26 to simplify and to improve the effectiveness of the connection between the respective components. It is desirable to position the insert assembly 42 along a sleeve axis 68 and with respect to the receiver/dryer housing 26 such that the standoff 64 properly engages the end section 66 of the dryer element 34. Additionally, it is desirable to position the insert assembly 42 such that the filter portion 46 is aligned with the second opening 36 of the receiver/dryer housing 26 and such that the refrigerant is able to flow across the core 12. The present invention provides a connection means between the receiver/dryer housing 26 and the insert assembly 42 that is easily and effectively adjustable, a threaded engagement. However, due to the relatively large size of the header, it may be difficult to form threads on the inner surface of the receiver/dryer housing 26. Therefore, the sleeve 48 is provided with interior threads 70 for engagement with the threaded portion 60 of the insert assembly 42.

The sleeve 48 preferably forms a press-fit engagement within the receiver/dryer housing 26. Therefore, an inner surface 72 of the receiver/dryer housing defines a receiver/dryer housing diameter 74, while an outer surface 76 of the sleeve 48 defines a sleeve diameter 78, and wherein the receiver/dryer housing diameter 74 is slightly smaller than or equal to the sleeve diameter 78. After being connected in the press-fit engagement, the receiver/dryer housing 26 and the sleeve 48 are also preferably brazed together to form a more secure connection.

In order to ease the insertion of the sleeve within the receiver/dryer housing 26, the sleeve upper portion 80 includes a varying outer diameter 82. More specifically, the sleeve upper portion 80 is tapered inwardly such that the outer diameter of the sleeve upper portion 80 is less than the receiver/dryer housing diameter 74, thus easing insertion. The varying outer diameter 82 shown in FIGS. 1 and 2 is an arcuate surface.

The varying outer diameter 82 of the sleeve 48 also improves the flow of the refrigerant into the insert assembly 42 by creating a relatively smooth flow of the refrigerant. More specifically, the sleeve upper portion 80 includes a sleeve opening 84, the plug portion 44 includes a plug opening 86, and the respective inner diameters of the openings 84, 86 are about equal to each other. The about equal inner diameters 84, 86 minimize leaks in the insert assembly 42 and cause the refrigerant flow through the insert assembly 42 to be relatively smooth.

The sleeve 48 further includes an opening 88 that is aligned with the receiver/dryer housing second opening 36. This opening 88 allows the refrigerant to flow into the second manifold chamber 38. The respective openings 36, 88 are preferably the same shape and size as each other, and more preferably are both circularly shaped. Alternatively, the sleeve opening 88 may be larger than the receiver/dryer housing second opening 36 such that the respective openings 36, 88 are aligned at various angles and axial positions between the sleeve 48 and the receiver/dryer housing 26.

In order to further locate the sleeve 48 within the receiver/dryer housing 26, the sleeve 48 shown in FIGS. 1 and 2 includes a shoulder portion 90 having a shoulder diameter 92 greater than the sleeve diameter 78. The shoulder portion 90 abuts the receiver/dryer housing 26 to prevent the sleeve 48 from being inserted too far within the receiver/dryer housing 26. The plug portion 44 further includes a plug portion shoulder 94 in order to engage the sleeve shoulder portion 90 and form a fluid-tight seal.

The sleeve 48 is preferably a stamp-formed component, but it may be formed by other appropriate means, such as machining. Furthermore, the sleeve threaded portion 70 is preferably roll-formed in order to reduce stress risers in the material and to minimize undesired gauling of the sleeve 48. The reduced gauling leads to a lower torque requirement for insertion of the filter/plug assembly 50 within the sleeve 48. The use of a relatively soft material for the sleeve, such as a 3000 Series Aluminum, makes the step of roll-forming the threaded portion 70 especially viable. Typically, harder aluminum, such as a 6000 Series Aluminum, requires the step of machine-forming the threaded portion. Machine-forming removes material, whereas roll-forming displaces material without substantial removal.

The sleeve upper portion 80, in particular the sleeve varying outer diameter 82, is preferably formed before the sleeve 48 is inserted within the receiver/dryer housing 26. The varying outer diameter 82 is preferably formed simultaneously with the formation of the sleeve 48. For example, the sleeve 48 may be formed by stamping a material to form a sleeve having a varying outer diameter. Alternatively, the varying outer diameter 82 may be formed after the body of the sleeve is initially formed. Similarly, the shoulder portion 90 of the sleeve 48 may be formed simultaneously with the formation of the sleeve 48 or it may be formed after the body of the sleeve 48 is initially formed.

The sleeve opening 88 is also preferably formed before the sleeve 48 is inserted within the receiver/dryer housing 26. Also, the sleeve opening 88 may be formed by punching material out of an initially-formed sleeve or it may be formed during the initial formation of the sleeve 48.

It is therefore intended that the foregoing detailed description be regarded as illustrative rather than limiting, and that it be understood that it is the following claims, including all equivalents, that are intended to define the spirit and scope of this invention. 

1. A heat exchanger for a vehicle comprising: a core having a set of flow tubes through which fluid may flow; and a header connected to the set of flow tubes to be in fluid communication therewith, the header including: a receiver/dryer housing in fluid communication with the set of flow tubes, the receiver/dryer housing enclosing a dryer element and having an inner surface defining a receiver/dryer inner diameter; and an insert assembly received within the receiver/dryer housing, the insert assembly including: a sleeve having a substantially smooth outer surface defining a sleeve outer diameter; a filter portion received within the sleeve so as to be in fluid communication with the receiver/dryer housing; and a plug portion configured to form a substantially fluid-tight seal with the sleeve; wherein the receiver/dryer inner diameter and the sleeve outer diameter are substantially equal to each other.
 2. A heat exchanger as in claim 1, wherein the sleeve further includes a threaded inner surface configured to engage a threaded outer surface of the plug portion of the insert assembly.
 3. A heat exchanger as in claim 1, wherein the sleeve is a stamped sleeve.
 4. A heat exchanger as in claim 1, wherein the sleeve further includes a sleeve first portion having a sleeve first inner diameter and a sleeve second portion having a sleeve second inner diameter, wherein the sleeve second inner diameter is greater than the sleeve first inner diameter.
 5. A heat exchanger as in claim 4, wherein the sleeve includes an inserted end and an outer end and the first portion is adjacent to the inserted end.
 6. A heat exchanger as in claim 5, wherein the filter portion defines a filter outer diameter being substantially equal to the sleeve first inner diameter.
 7. A heat exchanger as in claim 6, wherein the sleeve first inner diameter is a varying diameter along a sleeve central axis.
 8. A heat exchanger as in claim 7, wherein the varying diameter includes an arcuate shape.
 9. A heat exchanger as in claim 1, wherein the sleeve includes a shoulder portion having a sleeve second outer diameter being greater than the sleeve outer diameter.
 10. A heat exchanger as in claim 9, wherein the shoulder portion abuts the receiver/dryer housing.
 11. A heat exchanger as in claim 1, wherein at least one of the filter portion and the plug portion includes a standoff portion engaging the dryer element.
 12. A heat exchanger as in claim 11, wherein the filter portion and the plug portion form a filter/plug assembly.
 13. A heat exchanger as in claim 12, wherein the filter/plug assembly is constructed of Nylon
 66. 14. A heat exchanger as in claim 13, wherein the filter/plug assembly is a unitary, single component.
 15. A heat exchanger as in claim 12, wherein the filter/plug assembly includes a sealing ring forming a second substantially fluid-tight seal with the sleeve.
 16. A heat exchanger as in claim 15, wherein the sealing ring includes an arcuate outer surface.
 17. A heat exchanger as in claim 1, wherein the receiver/dryer housing and the insert assembly are connected by a brazed connection.
 18. A heat exchanger as in claim 1, wherein the sleeve is a stamped component.
 19. A heat exchanger as in claim 1, wherein the sleeve is constructed of 3000 Series aluminum.
 20. A method of assembly of a heat exchanger for a vehicle, the method comprising: providing a core having a set of flow tubes; and connecting a header to the set of flow tubes, the header having a receiver/dryer housing in fluid communication with the set of flow tubes, the receiver/dryer housing receiving a dryer element and having an inner surface defining a receiver/dryer inner diameter; inserting a sleeve within the receiver/dryer housing so as to form a press-fit engagement between the sleeve and the receiver/dryer housing, the sleeve having a substantially smooth outer surface defining a sleeve outer diameter; inserting a filter portion within the sleeve such that the filter portion is in fluid communication with the receiver/dryer housing; inserting a plug portion within the sleeve such as to form a substantially fluid-tight seal with the sleeve; and brazing the sleeve to the receiver/dryer housing.
 21. A method as in claim 20, further comprising the step of stamp-forming the sleeve.
 22. A method as in claim 21, further comprising: forming internal threads on an inner surface of the sleeve; and forming external threads on an outer surface of the plug portion such that the internal threads and the external threads form a threaded engagement.
 23. A method as in claim 22, wherein at least one of the internal threads and the external threads is roll-formed. 